There are big differences between the two revisions. The biggest one is, one is using Wifi/BT over USB and the other SDIO, which requires the sdio overlay. The reason for BT not working on Armbian, I have yet to figure out. Like I said before, it works on (my personal) a more minimal build;
Debian GNU/Linux trixie/sid 6.12.26 #1 Sun May 4 17:50:23 EDT 2025 aarch64
BananaPi BPI-M4-Zero v2
── DISK
Filesystem Size Used Avail Use% Mounted on
/dev/mmcblk2p2 29G 2.8G 26G 10% /
/dev/mmcblk2p1 466M 74M 363M 17% /boot
── NETWORK
Hostname: bananapim4zero
Wireless: wlan0 UP 10.0.0.XX
Bluetooth: hci0 AC:6A:A3:3B:D9:D6
── SYSTEM
Processor: Cortex-A53 @ 1416MHz 52°C
Frequency: 1416MHz
Online: 0-3
Governor: performance
Memory: 3.8G 199M
Entropy: 256
Uptime: 15:13:05 up 4 min, 1 user, load average: 0.01, 0.06, 0.
It is hard for me to determine the reasons BT doesn't work, as the patching is very extensive. If it is even the patching?
And yes I include the BT node in the overlay; https://github.com/armbian/build/blob/main/patch/kernel/archive/sunxi-6.12/patches.armbian/Add-BananaPi-BPI-M4-Zero-overlays.patch#L267
As for HDMI audio and GPU, the PR I posted a link to corrects this. In future releases and rolling (give it a day) it should now work. Although I think I need to now add my changes to the 6.14.y branch? I'll check.